Fifth Wheel Lock Verification Using Magnetic Flux Sensing

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Solution Overview

Problem

Existing fifth wheels may not fully or properly lock onto the kingpin, leading to inadvertent disengagement during towing, and components wear over time, causing vibrations and 'slack' issues, without effective systems to verify proper locking or detect wear.

Innovation Solution

A system using sensors and a controller to determine and verify the operational state of a fifth wheel by sensing magnetic flux from a magnet on a movable component, logging proper locking, and detecting wear, with indicators alerting operators to any issues.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a mechanical locking mechanism is used for the fifth wheel, then the locking function is achieved, but there is no verification system to confirm proper locking

Engineering Contradiction:
Improvelocking verificationVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent implements a feedback system where sensors detect the position of the movable component (jaw or wedge) and provide signals to a controller. The controller processes these signals and provides visual or audible feedback to confirm whether the fifth wheel is properly locked. This feedback mechanism resolves the contradiction by adding verification capability without excessive complexity, using straightforward sensor-controller-indicator architecture.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent replaces manual verification of the locking mechanism with automated sensor-based detection. Instead of requiring operators to physically inspect the mechanical components, magnetic sensors or Hall effect sensors detect the position of magnetized components, and electronic controllers process this data. This substitution of mechanical inspection with electronic sensing and processing achieves reliable verification while maintaining reasonable system complexity.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If no wear detection system is implemented, then the fifth wheel components wear over time causing vibrations and slack issues

Engineering Contradiction:
Improvewear detectionVSAvoidmonitoring system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent incorporates sensors that continuously monitor the position and movement characteristics of the locking components. By analyzing the travel distance and position variations of the jaw or wedge over time, the system detects wear patterns. This feedback approach enables wear detection by comparing actual component positions against expected ranges, providing reliability monitoring without requiring complex diagnostic systems.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The fifth wheel system performs self-monitoring through integrated sensors that track the operational state of its own components. The controller analyzes sensor data to detect wear conditions, eliminating the need for separate external monitoring equipment. This self-service capability achieves wear detection while minimizing additional system complexity, as the monitoring function is embedded within the existing control architecture.

Inventive Principle:
Principle #25Self-service

3Measurement precision

If manual inspection of locking components is required, then operators must physically check the fifth wheel, but this is time-consuming and may be missed

Engineering Contradiction:
Improvelocking state detectionVSAvoidinspection time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent replaces manual physical inspection with automated sensor-based detection systems. Magnetic sensors or Hall effect sensors continuously monitor the position of magnetized components on the jaw or wedge, providing precise measurement of the locking state without requiring operator intervention. This substitution achieves high measurement precision while eliminating inspection time loss, as the system operates continuously and provides immediate status information through visual or audible indicators.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent implements continuous monitoring of the locking state through sensors that operate throughout the entire operational cycle. Rather than periodic manual checks, the sensor system provides uninterrupted detection of component positions, ensuring the locking state is always known. This continuous action maintains measurement precision while eliminating time loss associated with intermittent manual inspections, as verification occurs automatically and continuously.

Inventive Principle:
Principle #20Continuity of useful action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Ensures the fifth wheel is properly locked and alerts operators to wear, reducing the risk of disengagement and vibrations, providing a detailed log for fleet management and liability defense.

Implementation Method 1

sensing, with at least one sensor, magnetic flux caused by a magnet on a movable component movable to lock the fifth wheel to a kingpin of a towed vehicle, determining an end position of the movable component based on the magnetic flux

Methodology Applied
Scientific EffectMagnetic flux sensing: Magnetic Field

Data Source

PatentUS20250276549A1Apparatuses, systems, and methods for determining and verifying operational states of fifth wheels
Publication Date: 2025.09.04 FONTAINE FIFTH WHEEL CO
  • US20250276549A1 patent drawing
  • US20250276549A1 patent drawing
  • US20250276549A1 patent drawing

AI summary

A method of tracking operational state of a fifth wheel includes sensing, with a sensor, movement of a movable component of the fifth wheel that moves as the fifth wheel locks onto a kingpin of a towed vehicle and determining, with a controller having a memory, an operational state of the fifth wheel based on the sensed movement of the movable component. The method also includes logging the operational state of the fifth wheel on the memory such that operation and/or wear of the fifth wheel is observable over time.